The separation of the solids from the liquid of a suspension has long been a problem in many fields of human endeavor. Large settling ponds have been used wherein the suspension was allowed to stand until the solid had settled to the bottom, leaving the liquid clear and ready to be removed. An improvement on these ponds was the Dorr pond wherein the suspension is flowed very slowly from an inlet in the center of the pond outward to the periphery of the pond. During this very slow motion, the solids settle to the bottom and the clarified liquid flows over a peripheral levee around the pond into a catch basin or trough.
Furthermore, liquid-solid suspension separators have been invented which are much smaller in volumetric size than the Dorr settling ponds while still retaining the separating capacity of the larger settling ponds. In general these more compact separators are built according to one of two basic designs, the inclined plane design and the fixed vane design.
Basically, in the inclined plane design, the separator has a multiplicity of fixed, equally spaced, parallel, planar surfaces, extending from side to side of the separator while extending from top to bottom of the separator at a pre-selected incline angle. The suspension is then run through these separators in such a fashion so as to be divided into many flow paths between the fixed, planar surfaces.
It is known that the contacting of "false bottoms", such as these planar surfaces, will cause the gravitational separation of the liquid from the solid of the suspension at a much faster rate than in settling ponds. The solids are generally denser than the liquid. Thus, upon separation from the liquid these denser solids slide down these false bottoms, or inclined planar surfaces, to the bottom of these more compact separators where they are collected. For examples of these type of separator see U.S. Pat. Nos. 3,552,554; 3,494,475; and 3,794,167.
The fixed vane type of compact separator is similar to the inclined plane design in that it offers a multiplicity of false bottoms to a flowing suspension, and in that the vanes are permanently affixed within the separator at predetermined positions. Unlike the planes of the inclined plane type of separator, the vanes of the fixed vane type do not extend the length of the separator from top to bottom.
In any event, both of these types suffer several disadvantages.
For example, to construct a suitable separator, it is usually necessary for the manufacturer to take a sample of the particular suspension to be separated, and then fabricate the separator according to the parameter of the proposed flow rate of the suspension and the properties of the particular suspension.
In any event once these types of separators are fabricated their false bottoms are permanently fixed in place and can not be readily adjusted in field usage as changing conditions sometimes dictate.
It would be advantageous to have a liquid-solid separator which is readily field adjustable. Moreover, it would be advantageous to have a method wherein settling pond separators such as Dorr pond separators could be improved. These and other advantages are realized in the present invention.